Elongate medical tools including printed circuit boards

ABSTRACT

A tool adapted for insertion into a physiological lumen of a patient is provided. The tool includes a hub, a core extending distally from the hub, and a printed circuit board (PCB) assembly. The PCB assembly includes a PCB substrate coupled to the core and an electronic component disposed on the PCB substrate and electrically coupled to the hub. The tool further includes an outer sheath disposed about each of the core and the PCB assembly. The PCB substrate may be in the form of a ring disposed at a distal end or about the core or may be a flexible PCB substrate adapted to be wrapped about the core and coupled to the core using an adhesive backing.

FIELD OF THE INVENTION

Aspects of the present disclosure relate to catheters and, morespecifically, to catheters including sensors and leads for conductingvarious medical procedures.

BACKGROUND

Various diagnostic and therapeutic procedures in or on the body of apatient, such as in the circulatory system, heart chambers, thebronchial tree or the like, may be performed or facilitated by insertinga catheter or similar elongate medical tool, such as a catheter or guidewire into a physiological lumen and thereafter navigating the diagnosticor therapeutic tool to the target anatomical site.

One method for maneuvering a catheter/guide wire involves the use offluoroscopy to track the position of a catheter/guide wire, duringnavigation or ablation. Another method of maneuvering a catheter andguide wire to an operational site is to place one or more positionsensors/leads on the catheter and guide wire, track the sensors with anavigation system, and display a reap time or rendered image of thecatheter/guide wire for the clinician manipulating the catheter/guidewire to view.

In many medical procedures, various physiological and location datawithin the body of a patient need to be monitored and analyzed. The rawsignal generated by the sensor located within the body is transmitted toan external device, in which the signal is re-translated intophysiological data, which may be subsequently processed, displayed(e.g., on a monitor), and/or saved or otherwise stored. In addition toor instead of sensors for collecting and processing location-relateddata, catheters may further include electrodes, sensors, or otherelectrical components for performing various other tasks including,without limitation, ablation, pacing and/or sensing of cardiac tissue,measurement of electrical activity within tissue, and the like.

It is with the foregoing in mind that the following concepts wereconceived and developed.

SUMMARY OF THE DISCLOSURE

In one aspect of the present disclosure, a too adapted for insertioninto a physiological lumen of a patient is provided. The tool includes ahub, a core extending distally from the hub, and a printed circuit board(PCB) assembly. The PCB assembly includes a PCB substrate coupled to thecore and an electronic component disposed on the PCB substrate andelectrically coupled to the hub. The tool further includes an outersheath disposed about each of the core and the PCB assembly an outersheath disposed about each of the core and the PCB assembly.

In one implementation, the PCB substrate is flexible and wrapped about aportion of the core. In such implementations, the PCB substrate mayinclude an adhesive backing and may be coupled to the core by theadhesive backing. The PCB assembly may further include a terminal pointand a trace extending along the PCB substrate to electrically couple theterminal point to the electronic component, the terminal point beingfurther electrically coupled to the hub such that the electroniccomponent is electrically coupled to the hub. In such implementations,the PCB substrate may extend distally from a proximal end of the coreand the terminal point may be disposed at the proximal end of the coresuch that the electronic component is disposed distal the terminalpoint.

In another implementation, the electronic component is an electrode. Insuch implementations, the electrode may be disposed at a distal end ofthe core. The electrode may also be exposed through the outer sheath.

In yet another implementation, the PCB substrate has a ring shape. Insuch implementations, the PCB substrate may be coupled to a distal endof the core. The ring shape may be any of a complete ring, a split ring,and a multi-part ring. In certain implementations, the ring-shaped PCBsubstrate is coupled to the distal end of the core by a sheath disposedabout each of the core and the PCB assembly.

In still another implementation the tool is one of a guidewire and acatheter.

In yet another implementation, the electronic component is one of anelectrode and a sensor.

In another aspect of the present disclosure, a method of assembling atool adapted for insertion into a physiological lumen of a patient isprovided. The method includes obtaining a core having an elongate shapeand disposing a printed circuit board (PCB) assembly onto the core, thePCB assembly including a PCB substrate and an electronic componentdisposed on the PCB substrate. The method further includes coupling thePCB substrate to the core, electrically coupling the electroniccomponent to a hub coupled to the core and applying an outer sheathabout the core and the PCB assembly.

In one implementation, the PCB substrate includes an adhesive backingand coupling the PCB substrate to the core comprises bonding the PCBsubstrate to the core using the adhesive backing.

In another implementation, applying the outer sheath about the core andthe PCB assembly couples the PCB substrate to the core.

In yet another implementation, the method further comprises, afterapplying the outer sheath, removing a portion of the outer sheath toexpose the electronic component.

In still another implementation, the core is a tubular core and the toolis a catheter.

In yet another aspect of the present disclosure a catheter assembly isprovided. The catheter assembly includes a hub, a tubular core extendingdistally from the hub., and a PCB assembly. The PCB assembly includes aPCB substrate coupled to the tubular core by an adhesive backing of thePCB substrate. The PCB assembly further includes a first electrodedisposed on the PCB substrate and electrically coupled to a firstterminal point of the PCB assembly and a second electrode disposed onthe PCB substrate and electrically coupled to a second terminal point ofthe PCB assembly. The catheter assembly further includes an outer sheathdisposed about each of the tubular core and the PCB assembly. Each ofthe first terminal point and the second terminal point are electricallycoupled to the hub and each of the first electrode and the secondelectrode are exposed through the outer sheath.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a catheter 10 in accordance with animplementation of the present invention.

FIG. 2 is a cross-sectional side view of a distal end of another examplecatheter in accordance with the present disclosure.

FIG. 3 is a cross-sectional side view of a distal end of yet anotherexample catheter in accordance with the present disclosure.

FIGS. 4A and 4E are schematic illustrations of a ring assembly for usein the catheters of FIGS. 2 and 3.

FIGS. 5A and 5B are end and side views, respectively, of a ring assemblyincluding a printed circuit board (PCB) substrate in the shape of acomplete ring.

FIGS. 6A and 6B are end and side views of another ring assemblyincluding a PCB substrate in the shape of a split ring.

FIGS. 7A and 7B are end and side views of yet another ring assemblyincluding a multi-part PCB substrate.

FIGS. 8A-8F are cross-sectional side views of a catheter at variousstages of assembly of the catheter.

FIG. 9 is a flow chart illustrating a method for assembling a catheterin accordance with FIGS. 8A-8F.

FIG. 10 is a schematic illustration of a PCB assembly including aflexible PCB substrate.

FIGS. 11A and 11B are side views of a distal end of a tool including thePCB assembly of FIG. 10.

FIG. 12 is a schematic illustration of another flexible PCB assembly inaccordance with the present disclosure.

FIGS. 13A and 13B are side views of a tool including the PCB assembly ofFIG. 12 without an outer sheath.

FIGS. 14A and 14B are side views of the tool of FIGS. 13A and 13Bincluding the PCB assembly of FIG. 12 and further including an outersheath.

FIG. 15 is a schematic illustration of an alternative PCB assemblyaccording to the present disclosure.

FIG. 16 is a flow chart illustrating another method for assembly a toolin accordance with the present disclosure, the tool including a flexiblePCB assembly.

DETAILED DESCRIPTION

Implementations of the present disclosure involve medical toolsincluding printed circuit board (PCB) elements. Although not limited toany particular type of tool, such tools may include catheters, guidewires, and other elongate tools for insertion into physiological lumensof a patient and which include electronic components (e.g., electrodes,sensors, etc.) for performing various functions as described below. Asfurther described below, by incorporating the various electroniccomponents into a PCB, significant improvements in manufacturingefficiency and quality may be achieved.

As previously noted, catheters, guide wires, and other similar tools mayinclude various electronic components for performing such datacollection and analysis. As previously noted, such components may beused to locate the tool, obtain measurements from within a physiologicallumen, and/or stimulate tissue adjacent the tool. Regardless of thefunction of such components, each generally requires the exchange ofelectrical current/signals between the component and a proximal end ofthe tool. In certain implementations, such signals may be relatively lowenergy and correspond to sensor measurements or similar signalsexchanged between components of the tool. Alternatively, or in additionto such signals, the electrical components may also be adapted toconnect to and deliver power from a power source for purposes ofstimulating or ablating tissue or performing similar tasks.

In light of the foregoing, a given tool may include sensors and/orelectrodes for obtaining measurements or delivering energy to adjacenttissue, but also includes cables, wires, leads, etc. for transmittingelectrical signals to/from the sensor or electrode. Such conductors aregenerally routed along the tool such that during use, they extend outfrom the physiological lumen within which the tool is disposed anextern& computing device. The conductors are generally extended along orare otherwise supported by an inner structure (generally referred toherein as a “core” or a “tubular core” in the context of catheter-basedapplications) which may include a metal wire, a braided wire, a plastictube, or combinations thereof (e.g., a plastic tube including anembedded braided wire). In addition to supporting the various componentsof the tool, the core may provide structural integrity to the tool andenable manipulation of the tool (e.g., by being coupled to pull rings ofthe tool).

Electrical current typically enters or exits the tool at an electricalconnection attached to the proximal end of the tool and, as a result,generally requires that multiple sections of the tool be electricallyisolated from each other and the surrounding tissue. For example, suchisolated areas need to be protected from ingress of bodily fluid thatmay result in a short or other conductivity issues.

In one specific example, a catheter may include a pair of electrodesdisposed at its distal end for measuring electrical activity in adjacenttissue and/or stimulating the tissue. The use of such electrodes maypresent various manufacturability concerns due to the variation presentwhen the electrode is adhered to the underlying polymer of the catheter.Also, conventional approaches to manufacturing such catheters can becomplicated and time consuming. For example, the distal assembly mayrequire the folding of the electrodes and soldering of associated wireswhile maintaining a certain gap between the electrodes. Moreover, manyconventional assembly processes are manual and tedious, directlyimpacting the ultimate cost and effectiveness of the catheter.

Various aspects of the present disclosure are directed to simplifyingthe manufacturing process of elongate tools including electroniccomponents and, as a result, to improving manufacturing efficiency andimproving quality by reducing part-to-part variation. More specifically,aspects of the present disclosure are directed to catheters and similarelongate tools that include PCBs. In at least certain implementations,such PCB assemblies are in the form of a ring that may be coupled to adistal end of a core of a catheter (or similar tool) or otherwisedisposed at various locations along the catheter. The ring assembly maybe coupled to the core using various techniques; however, in oneimplementation, a polymer sleeve is disposed about each of the ringassembly and the core and heat-shrunk/reflowed to couple the ringassembly to the core. In addition to coupling the ring assembly andcore, the polymer sleeve adds rigidity and electrical insulation to thedistal end of the catheter.

In another implementation of the present disclosure, the PCB is in theform of a flexible PCB that may extend along a portion of the core. Inone implementation, the flexible PCB is adapted to be coupled to adistal end of the core while in other implementations the flexible PCBextends along a greater length of the core, including substantiallyalong the full length of the core. Although the flexible PCB may becoupled to the core using various methods, in at least oneimplementation, the flexible PCB is adhesive-backed such that, duringassembly, the flexible PCB may be laid or otherwise run along the lengthof the core and held in place by the adhesive. Subsequently, an outersheath may be heat-shrunk/reflowed over the flexible PCB.

FIG. 1 is a side view of a catheter 10 in accordance with animplementation of the present invention. The catheter 10 may be used inany medical procedure requiring catheterization and that includes is notintended to be limited to any particular type of catheter orcatheterization procedure. The catheter 10 includes a catheter shaft 12and a hub 14. The catheter shaft 12 has a proximal portion 16 and adistal portion 18. In some embodiments, the catheter shaft 12 may, forexample, be any catheter shaft, whether known now or later developed,for use in the delivery and/or deployment of implantable medical devices(such as medical electrical leads, stents and implantable sensors) orother catheterization procedures (such as drug delivery, mapping andablation).

The catheter shaft 12 may be formed of a single layer or two or moredistinct layers that are formed of the same or different materials. Insome implementations, the catheter shaft 12 may include reinforcingmaterials such as metallic or polymeric braids. The catheter shaft 12may be formed of one or more thermoplastic polymers such as, but notlimited to polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene(ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, forexample, DELRIN™ available from DuPont), polyether block ester,polyurethane, polypropylene (PP), polyvinylchloride (PVC),polyether-ester (for example, ARNITEL™ available from DSM EngineeringPlastics), ether or ester based copolymers (for example,butylene/poly(alkylene ether) phthalate and/or polyester elastomers suchas HYTREL™ available from DuPont), polyamide (for example, DURETHAN™available from Bayer or CRISTAMID™ available from Elf Atochem),elastomeric polyamides, block polyamide/ethers, polyether block amide(PEBA, for example, available under the trade name PEBAX™, silicones,polyethylene (PE), Marlex high-density polyethylene, Marlex low-densitypolyethylene, linear low density polyethylene (for example REXELL™polyester, polybutylene terephthalate (PBT), polyethylene terephthalate(PET), polytrimethylene terephthalate, polyethylene naphthalate (PEN),polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI),polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polyparaphenylene terephthalamide (for example, KEVLAR™), polysulfone,nylon, nylon-12 (such as GRILAMID™ available from EMS American Grilon),perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefin,polystyrene, epoxy, polyvinylidene chloride (PVdC), polycarbonates,ionomers, biocompatible polymers, other suitable materials, or mixtures,combinations, copolymers thereof.

In some implementations, the catheter shaft 12 or at least an outerlayer thereof may be formed of a polyether block amide such as PEBAX™. Avariety of PEBAX™ materials are available, having varying performanceparameters such as hardness/stiffness as indicated by the durometervalue of a particular PEBAX™ polymer. In one particular implementation,the catheter shaft 12 or an outer layer thereof may be formed of PEBAX™having a Shore hardness of about 72 D.

In some implementations, as illustrated, the hub 14 may include a bodyportion 20 and a strain relief portion 22. The body portion 20 mayinclude a lumen (not shown) in communication with one or more lumens(not shown) extending through the catheter shaft 12. The body portion 20may also include one or more luer fittings to accommodate attachment offluid lines and the like. The body portion 20 may be configured to actas a handle or grip and thus may include structure (not illustrated)that facilitates grasping the hub 14. The hub 14 may be a breakaway orsplittable hub.

In some implementations, the strain relief portion 22 may be integrallymolded with the body portion 20. The strain relief portion 22 mayinclude an inner component that is integrally molded or otherwise formedwith the body portion 20 and one or more external components that helpprovide desired characteristics such as a flexibility/stiffness gradientbetween the catheter shaft 12 and the hub 14.

The hub 14 may be formed of a variety of different materials. Suitablematerials include but are not limited to the materials discussed abovewith respect to the catheter shaft 12. In some cases, the hub 14 may beformed of a material that does not bond well, either adhesively or viawelding, to the material used to form the catheter shaft 12.

In some embodiments, the hub 14 may be formed of a thermoset polymer. Insome embodiments, at least part of the hub 14, such as the body portion20 and an inner component of the strain relief portion 22 may be formedof a styrene-butadiene copolymer available commercially under theK-Resin™ name. The catheter shaft 12, or at least an outer layerthereof, may be formed of a material that is difficult to secure to thehub 14 using an adhesive or by directly welding the two together. Insome cases, the addition of a mechanical connection between the cathetershaft 12 and the hub 14 may be beneficial.

As illustrated in FIG. 1, the catheter 10 may include various electricalcomponents adapted to perform various functions. The electricalcomponents may include, for example and without limitation, varioussensors and electrodes disposed at different locations along thecatheter shaft 12 to provide location data, measure physiologicalactivity, provide stimulation, ablate tissue, or perform or facilitateany other of a wide range of functions and activities. The catheter 10of FIG. 1, for example, includes each of a pair of ring electrodes 24,26 disposed at an intermediate location along the catheter shaft 12between the proximal portion 16 and the distal portion 18. In onenon-limiting example, each of the ring electrodes 24, 26 may at leastone of deliver electrical stimulation to adjacent tissue or measureelectrical activity of such tissue. The catheter 10 may also include adistal tip assembly 28 that further includes additional sensors and/orelectrodes for performing any of the foregoing functions.

To facilitate functions of the various electrical components of thecatheter 10, the hub 20 may include one or more connectors, such asconnectors 30 and 32. Each connector 30, 32 may be electrically coupledto a respective sensor, electrode, or other component of the catheter 10via a cable, wire, lead, or similar conductor or conductors (not shown).In general, the connectors 30, 32 may be communicatively coupled toother devices configured to transmit electrical signals to theelectrical components of the catheter 10 and/or receive electricalsignals from the electrical components of the catheter 10. Such devicesmay include, for example and without limitation, power sources,computing devices, data recorders, displays, and the like. Eachconnector 30, 32 may be electrically coupled to one, two, or any numberof electrical components of the catheter 10. For example, in oneimplementation, each of the ring electrodes 24, 26 may be electricallycoupled to the connector 30, which in turn may be electricallycoupleable to a computing device capable or recording and/or storingdata corresponding to signals from the ring electrodes 24, 26.

Tools Including PCB Assembly Tips

With the foregoing general description of the catheter 10 in mind, oneaspect of the present disclosure is directed to improved distal tipassemblies and methods of manufacturing catheters including such distaltip assemblies. As described below in further detail, the distal dipassemblies described herein are generally formed as an integratedprinted circuit board (PCB) assembly that is connected to wires, leads,or similar conductors of the catheter. The PCB assembly is then coupledto the distal end of the catheter.

FIG. 2 is a cross-sectional view of an example catheter 200 inaccordance with the present disclosure and, more specifically,illustrates a distal end 201 of the catheter 200. The present disclosureis generally applicable to any catheter (or similar elongate tool, suchas a guide wire); accordingly, the catheter 200 and its components areprovided merely as an example and should not be viewed as limiting thescope of this disclosure.

As illustrated in FIG. 2, the catheter 200 generally includes a tubularcore 202 defining a primary lumen 204. The lumen 204 may vary in sizeand shape according to the particular application for the catheter 200;however, in general, the lumen 204 is sized and shaped to facilitateinsertion and translation of other tools therein.

In certain implementations, the catheter 200 may include a pull ring 206from which a pull wire 207 proximally extends. During use, tension onthe pull wire 207 may be varied to selectively deflect and/or straightenthe catheter 200 to facilitate steering or other manipulation of thedistal end of the catheter 200.

The catheter 200 may also include one or more conductors, such asconductor 208, extending along its length. The conductor 208 generallyfacilitates transmission of electrical signals along the length of thecatheter 200. In the implementation illustrated in FIG. 2, the conductor208 is illustrated as a single wire; however, it should be appreciatedthat the conductor(s) extending along the length of the catheter 200 maybe in any suitable configuration including, without limitation, singlewires and multi-wire cables. As shown, the tubular core 202 and the pullring 206 may be encapsulated by an outer layer or sheath 209.

As illustrated in FIG. 2, each of the pull wire 207 and the conductor208 are shown as being embedded within the tubular core 202; however, itshould be appreciated that any suitable arrangement of pull wires andconductors may be used in implementations of the present disclosure. Forexample, and without limitation, in certain implementations each of thepull wire 207 and the conductor 208 may be disposed on an externalsurface of the tubular core 202 and coupled to the tubular core 202,such as by applying/wrapping a sheath or similar layer about the core202, the pull wire 207 and the conductor 208. In other implementations,the conductor 208 and the pull wire 207 may be integrated into thetubular core 202. In still other implementations, the tubular core 202may be formed from multiple layers and the pull wire 207 and theconductor 208 may be disposed between adjacent layers of the tubularcore 202. It should also be appreciated that either or both of the pullwire 207 and the conductor 208 may be disposed within a lumen defined bythe tubular core 202 or within lumens embedded within the tubular core202 and either or both of the pull wire 207 and the conductor 208 may bedisposed in the same or respective lumens.

In implementations of the present disclosure, a PCB assembly 210 (alsoreferred to herein as a ring assembly 210) is disposed at a distal endof the catheter 200. The ring assembly 210 generally includes a printedcircuit board (PCB) substrate 212 on or within which various electricalcomponents are integrated. To prevent obstruction of the lumen 204, thePCB substrate 212 has an annular or similar tubular shape. For example,in certain implementations (such as illustrated in FIGS. 5A-6B), the PCBsubstrate may be in the form of a rigid or semi-rigid ring or splitring. As illustrated in FIGS. 7A-7B, the PCB substrate 212 may also bedivided into multiple discrete segments.

The PCB substrate 212 supports electrical components of the ringassembly 210 and may further include traces, contacts, and/or conductorsfor electrically connecting such components of the distal assembly 210to each other and/or to other components of the catheter 200. Forexample, the ring assembly 210 illustrated in FIG. 2 includes a contact214 to which the conductor 208 is electrically coupled. The ringassembly 210 further includes a pair of electrodes 218, 220 inelectrical communication with the contact 214 such that electricalsignals/electrical energy may be sent to or received from the electrodes218, 220.

Although the ring assembly 210 may be coupled to the core 202 in variousways, in the specific implementation illustrated in FIG. 2, the core 202and ring assembly 210 are joined by a coupling sleeve 222. As describedbelow in further detail in the context of FIGS. 8A-8F, coupling usingsuch an approach may include disposing the coupling sleeve 222 to extendalong each of the core 202 (including any outer sheath extending aroundthe core, such as the sheath 210, and/or pull ring that may be present,such as the pull ring 206) and the PCB substrate 212 of the ringassembly 210. Once so positioned, the coupling sleeve 222 may be heatshrunk/reflowed, thereby forming a joint between the tubular core 202and PCB substrate 212.

In other implementations, the ring assembly 210 may be disposed onto adistal end of the core 202. For example, FIG. 3 illustrates analternative implementation of a catheter 300 in which the core 202extends beyond the pull ring 206 and the PCB substrate 212 of the ringassembly 210 is sized to “cap” or otherwise be disposed on the distalend of the core 202. In such implementations, the PCB substrate 212 maybe coupled to the core 202 using any suitable method. Similar to theimplementation of FIG. 2, for example, the implementation of FIG. 3 alsoincludes a coupling sleeve 222 extending around and joining the PCBsubstrate 212 to the core 202 (or, more specifically, the sheath 212extending about the core 202). In other implementations, adhesives,ultrasonic welding, or any other suitable method of coupling componentsmay be used to join the PCB substrate 212 and core 202.

FIGS. 4A and 4B are elevation views of the PCB/ring assembly 210 ofFIGS. 2 and 3. As previously discussed, the ring assembly 210 generallyincludes a PCB substrate 212 on which various electrical components aredisposed. The ring assembly 210 further includes a pair of connectorcontacts 214, 216 coupled to respective electrodes 218, 220 by traces224, 226. In certain implementations, the electrodes 218, 220 may beplatinum electrodes; however, any suitable electrode material may beused.

It should be appreciated that the two-electrode ring assembly 210illustrated in FIGS. 2-4B is provided merely as an example and othervariations are contemplated as part of this disclosure. More generally,PCB assemblies in accordance with the present disclosure includeelectronic components (e.g., sensors, electrodes) disposed on a PCBsubstrate that is coupleable to a core of an elongate medical tool, suchas a catheter or guide wire. The term “core” is used herein to generallydescribe an underlying structure of the medical tool and may includetubular structures, solid structures, or any combination thereof. Inaddition to the electronic components, the PCB assembly may includeterminal points (e.g., contact pads) electrically connected to theelectronic components (e.g., by directly coupling of the terminal pointto the electronic component or by coupling the terminal point to theelectronic component by a trace or similar conductor). PCB assemblies inaccordance with the present disclosure are not limited to any particularnumber of electronic components or any particular arrangements of suchcomponents. Accordingly, to the extent any specific implementations arediscussed herein, such implementations should be considered merely asillustrative examples of aspects of this disclosure.

FIGS. 5A-7B illustrate different configurations of ring assemblies inaccordance with the present disclosure. FIGS. 5A and 5B illustrate aring assembly 500 consistent with that illustrated in FIGS. 4A and 4B.The ring assembly 500 includes a PCB substrate 512 in the form of aunitary ring. The ring assembly 500 further includes a pair of contacts514, 516 connected to respective electrodes 518, 520 by traces 524, 526.FIGS. 6A and 66 illustrate an alternative ring assembly 600 including aPCB substrate 612. Similar to the ring assembly 500 of FIGS. 5A-5B, thering assembly 600 further includes a pair of contacts 614, 616 connectedto respective electrodes 618, 620 by traces 624, 626. In contrast,however, the PCB substrate 612 includes a split 601 such that the ringassembly 600 may be “snapped” onto a catheter core or otherwisepermitted to expand to accommodate variations in catheter diameter.FIGS. 7A and 7B illustrate another alternative ring assembly 700 inwhich the PCB substrate is divided into two distinct halves 712A, 712B.Each half includes a respective contact 714, 716 with each contact 714,716 connected to an electrode 718, 720 by traces 724, 726. Althoughillustrated as including two halves, it should be appreciated that inother implementations, any number of suitable PCB substrate parts may beused.

Although the foregoing description generally refers to the ring-type PCBassemblies being disposed at a distal end of the catheter, it should beappreciated that such assemblies may be located at any location alongthe length of the catheter. Moreover, while the ring assemblies arediscussed as being used in conjunction with catheters, such ringassemblies may more generally be incorporated into any elongate body ortool. For example, and without limitation, a ring assembly may becoupled to and used in conjunction with a guide wire.

Manufacturing of Elongate Tools with PCB Assemblies

Elongate tools, such as catheters, including PCB assemblies inaccordance with the present disclosure may be manufactured in variousways; however, in general, the process of manufacturing such toolsincludes forming a primary tool body or shaft and disposing wiring alongthe tool body. The wiring is then electrically coupled to contacts ofthe PCB assembly, which, in turn, is disposed on a core of the tool.With the wiring connected and the PCB assembly in place, the PCBassembly is coupled to the core using one of various techniques.

FIG. 8A-8F illustrate an example assembly process for manufacturing anexample catheter 800 in accordance with the present disclosure.Additional reference is made to FIG. 9, which is a flow chart describinga method 900 in accordance with the assembly steps illustrated in FIGS.8A-8F.

Referring first to FIG. 8A and operation 902 of FIG. 9, a mandrel 802for assembling the catheter is prepared. Preparation of the mandrel 802may include, for example, disposing a sheath 804 about the mandrel. Thesheath 804 may generally be used to reduce friction between the mandrel802 and subsequent components slid onto the mandrel 802 during assemblyof the catheter. In one example implementation, the sheath 804 may beformed from polytetrafluoroethylene (PTFE), or a similar low-frictionmaterial.

As illustrated in FIG. 8B, with the mandrel 802 prepared with the sheath804, each of a pull ring 806, a conductor 808, and a tubular core 810may be assembled onto the mandrel 802 (operation 904). The process ofassembling the pull ring 806, conductor 808, and tubular core 810 mayvary in implementations of the present disclosure; however, in general,the process includes extending the tubular core 810 along the mandrel802, disposing the pull ring 806 on the mandrel 802, and running each ofthe conductor 808 and a pull wire 807 along the length of the tubularcore 810. It should be appreciated that extending the tubular core 810along the mandrel 802 may include disposing a pre-fabricated (e.g., anextruded) core along the mandrel, fabricating the core directly onto themandrel (e.g., by braiding thread onto the mandrel and subsequentlyapplying a layer of heat shrink), or any combination thereof. In certainimplementations, the tubular core has a multi-layer construction and thepull wire 807 and the conductor 808 may be disposed between adjacentlayers of the core 802. The pull wire 807 and the conductor 808 may alsobe disposed in a common, or respective lumens that are in turn coupledto the exterior of the tubular core 810 (e.g., by applying a layer ofshrink wrap) or that are embedded within the tubular core 810.

As illustrated in FIG. 8C, a PCB assembly 812 is subsequently disposedon the mandrel 802 distal the pull ring 806 and tubular core 810(operation 906) and the conductor 808 is electrically coupled to acontact 814 of the PCB assembly 812 (operation 908). Disposing the PCBassembly 812 over the mandrel 802 may include any of sliding the PCBassembly 812 onto a distal end of the mandrel 802, “snapping” the PCBassembly 612 onto the mandrel 802 (e.g., when using a split ringassembly, similar to that of FIGS. 6A-6B), or disposing multipleportions of the PCB assembly 812 about the mandrel 802 (e.g., when usinga multi-part ring assembly, similar to that of FIGS. 7A-7B). Aspreviously noted in the context of FIG. 3, the PCB assembly 812 may alsobe adapted to at least partially extend over the tubular core 810 and/orthe pull ring 806.

With the PCB assembly 812 in place and electrically coupled to theconductor 808, the PCB assembly 812 may then be coupled to the tubularcore 810 (operation 910). In one implementation, such coupling may beachieved by using a sleeve 816 formed from a heat-shrinkable material.As shown in FIG. 8D, for example, the sleeve 816 may be disposed about adistal end of the catheter 800 such that the sleeve 816 extends about aportion of each of the PCB assembly 812 and the tubular core 810. Asillustrated in FIG. 8E, a heating process may then be conducted toreflow/shrink the sleeve 816 about the tubular core 810 and the ringassembly 814, thereby coupling the tubular core 810 to the PCB assembly812. Although the sleeve 816 is illustrated as extending over only adistal portion of the core 810 and PCB assembly 812, it should beappreciated that the sleeve 816 may extend further over a proximalportion of the core 810 up to and including the full length of the core810.

As shown in FIG. 8E, following reflow of the distal sleeve 816, thedistal sleeve 816 may at least partially obstruct electrodes 818, 820(or similar components) of the PCB assembly 812. Accordingly, followingcoupling of the PCB assembly 812 to the tubular core 810, portions ofthe sleeve 816 may be removed to increase exposure of the electrodes818, 820 (operation 912). For example, and without limitation, removingportions of the sleeve 816 may include one of cuffing away or ablating(e.g., using a laser) portions of the sleeve 816. The catheter 800including the PCB assembly 812 may subsequently be removed from themandrel 802.

As previously noted, each of the sleeve 816 and layers of the core 810may be formed from a material capable of being heat shrunk/reflowed.Although various materials may be used in applications of the presentdisclosure, in at least certain implementations and without limitations,such a material may include a polyether block amide (e.g., PEBAX™).

Medical Tools Including Flexible PCB Assemblies

The PCB assemblies of the various foregoing examples were illustrated asincluding a PCB substrate having a substantially static shape and, morespecifically, a curved or circular shape conforming to the overall shapeof the catheter. However, it should be appreciated that in other aspectsof the present disclosure, the PCB assembly may be a more generalassembly formed from a flexible circuit that is wrapped around orotherwise coupled to a tubular core of the catheter.

FIG. 10 illustrates an example PCB assembly 1000 in the form of aflexible PCB. The PCB assembly 1000 generally includes a flexiblesubstrate 1002 to which various electronic components may be coupled. Asillustrated in FIG. 10, for example, the PCB assembly 1000 includes apair of electrodes 1004, 1006 coupled to respective contact pads 1008,1010 by corresponding traces 1012, 1014. Similar to the previouslydiscussed ring-type PCB assemblies, the electrodes 1004, 1006 are merelyintended as non-limiting examples of electronic components that may beincluded in the PCB assembly 1000.

FIGS. 11A and 11B are alternate side elevation views of a distal end1102 of a tool 1100 including the PCB assembly 1000 of FIG. 10. Morespecifically, FIG. 11A is a side elevation view of the tool 1100 from afirst perspective while FIG. 11B is a side elevation view of the too1100 from a perspective 180 degrees offset from the first perspective.Among other things, the tool 1100 may correspond to a catheter,guidewire, or similar elongate tool that may be inserted into aphysiological lumen of a patient to perform various functions. Asillustrated, the PCB assembly 1000 is disposed on a core 1104 of thetool 1100. During assembly, the PCB assembly 1000 may be disposed on thecore 1104 and electrically connected to other components of the tool1100. For example, the tool 1100 includes a pair of conductors 1106,1108 that are electrically coupled to the contact pads 1008, 1010 of thePCB assembly 1000 and extend along the length of the core 1104. Theconductors 1106, 1108 may in turn be connected to a computing device,power source, or other electrical component at a proximal end of thetool 1100.

As illustrated in FIGS. 11A-11B, the tool 1100 may include an outersheath 1110 that extends over each of the core 1104 and the PCB assembly1000. In at least one example implementation of the present disclosure,the tool 1100 may be assembled, in part, by disposing the PCB assembly1000 onto the core 1104, extending the conductors 1106, 1108 along thecore 1104, and electrically coupling the conductors 1106, 1108 to thePCB assembly 1000. Subsequently, the outer sheath 1110 may be extendedover the core 1104, the PCB assembly 1000, and the conductors 1106, 1108and heat shrunk/reflowed to shrink the outer sheath 1110 over the innercomponents of the tool 1100. In some implementations of the presentdisclosure, following application of the outer sheath 1110 and similarto FIG. 8F, above, at least a portion of the outer sheath 1110 may beremoved (e.g., by cutting or laser ablation) to expose components of thePCB assembly 1000. For example, in FIGS. 11A and 11B the electrodes1004, 1006 of the PCB assembly 1000 are exposed through the outer sheath1110. Accordingly, following heat-shrinking/reflowing of the outersheath 1110, the electrodes 1004, 1006 are free to interact with tissueadjacent the tool 1100 while the other components of the PCB assembly1000 and the tool 1100 (e.g., the contact pads 1008, 1010, the leads1012, 1014, and the conductors 1106, 1108) remain substantially coveredprotected by the outer sheath 1110.

In another aspect of the present disclosure, the general concept ofimplementing a flexible PCB for electronic components of a tool may beexpanded beyond a distally positioned assembly to include additionalelectrical components of the tool. FIG. 12, for example is a plan viewof a PCB assembly 1200 that may be incorporated into a catheteraccording to the present disclosure. In contrast to the distal tipassembly 1000 of FIG. 10, which is configured to be disposed at a distalend of a catheter, the PCB assembly 1200 is adapted to extend alongsubstantially the full length of a catheter lumen.

As illustrated in FIG. 12, the PCB assembly 1200 includes a PCBsubstrate 1202 which is formed from a flexible material. In one exampleimplementation, the PCB substrate 1202 may be formed from a polyimidefilm such as Kapton™.

Although other configurations are possible, the PCB assembly 1200further includes a pair of electrodes 1204, 1206 disposed at a distalend 1201 of the PCB assembly 1200 and a pair of corresponding contactpads 1208, 1210 disposed at a proximal end 1203 of the PCB assembly1200. Each of the electrodes 1204, 1206 is electrically coupled to oneof the contact pads 1208, 1210 by a respective trace 1212, 1214. Similarto previous implementations discussed herein, the electrodes 1204, 1206are merely provided as example electronic components and otherelectronic components (e.g., other electrodes and/or sensors) may beincorporated into the CB assembly 1200 instead of or in addition to theelectrodes 1204, 1206. In other implementations, the contact pads 1208,1210 may instead be replaced by a plug, terminal, or other connector.Alternatively, the traces 1212, 1214 may extend off of the PCB substrate1202 to facilitate electrical coupling of the traces 1212, 1214 to othercomponents of a tool.

Referring now to FIGS. 13A-14B, an example tool 1300 is illustratedincluding the PCB assembly 1200 of FIG. 12. More specifically, FIGS. 13Aand 14A are side elevation views of the tool 1300 from a firstperspective while FIGS. 13B and 14B illustrate are side elevation viewsof the tool 1300 from a perspective 180 degrees offset from the firstperspective. FIGS. 13A-13B each illustrates the tool 1300 without anouter sheath to more clearly illustrate the arrangement of the PCBassembly 1200 with respect to the remainder of the catheter. Incontrast, FIGS. 14A-14B include an outer sheath 1410 that substantiallycovers the PCB assembly 1200.

Referring to FIGS. 13A-13B, the PCB assembly 1200 is shown extendingalong a core 1304 of the tool 1300. More specifically, the PCB assembly1200 is disposed on the core 1304 such that the electrodes 1204, 1206are disposed at a distal end of the core 1304 and the contact pads 1208,1210 are disposed at a proximal end of the core 1304. Accordingly, eachof the traces 1212, 1214 extends along substantially the full length ofthe core 1304. As illustrated in FIGS. 13A-14B, in certainimplementations the electrodes 1204, 1206 may be spaced relative to eachother such that when coupled to the core 1304, the electrode 1204 isdisposed opposite the electrode 1206.

The PCB assembly 1200 may be coupled to the core 1304 in various ways.For example, in one implementation, the PCB substrate 1202 of the PCBassembly 1200 may be adhesive backed. In such implementations, assemblyof the tool 1300 may include forming or sizing the core 1304 andsubsequently laying the PCB assembly 1200 along the core 1304 with theadhesive disposed between the PCB substrate 1202 and the core 1304. Suchassembly may further include pressing or otherwise applying pressure tothe PCB assembly 1200 to ensure adequate bonding between the PCBsubstrate 1202 and the core 1304. In certain implementations, theadhesive may be at least partially heat activated such that assemblyfurther includes a step of heating/curing the adhesive after the PCBassembly 1200 has been disposed on the core 1304.

As illustrated in FIGS. 14A and 14B, following coupling of the PCBassembly 1200 to the core 1304, an outer sheath 1310 may be pulled overor otherwise disposed over the core 1304 and the PCB assembly 1200 andcut to size. The outer sheath 1310 may then be heat shrunk/reflowed suchthat the outer sheath 1310 warp more closely around the core 1304 andthe PCB assembly 1200. After wrapping of the outer sheath 1310, portionsof the outer sheath 1310 may also be removed (e.g., by cutting, laserablation, or other suitable method) to expose components of the PCBassembly 1200. For example, as illustrated in FIGS. 14A and 14B,portions of the outer sheath 1310 corresponding to each of theelectrodes 1204, 1206 and contact pads 1208, 1210 are removed to exposethe electrodes 1204, 1206 and contact pads 1208, 1210.

As previously noted, the PCB assembly 1200 may be adhesive-backed tofacilitate coupling of the PCB assembly to the core 1304 of the tool1300. However, in other implementations, the PCB assembly 1200 may becoupled to the core 1304 in other ways. For example, and withoutlimitation, in at least one implementation, the PCB assembly 1200 maynot include adhesive backing and may be retained in position by theouter sheath 1310 only. In other implementations, the PCB assembly 1200may be fixed to the core 1304 using, among other things, ties, clips,wire, or any other suitable coupling mechanism prior to application ofthe cuter sheath 1310.

The foregoing examples of distal tip and PCB assemblies generallyincluded electrodes adapted to be disposed at a distal end of acatheter. It should be appreciated, however, that other configurationsare contemplated within the scope of the present disclosure. FIG. 15,for example, is a plan view of a PCB assembly 1500 including a flexiblePCB substrate 1502 and various electrical components coupled to the PCBsubstrate 1502. Similar to previous implementations, the PCB substrate1502 is adapted to be coupled to a core or similar elongate body of acatheter or other tool.

While the PCB assembly 1500 includes a pair of distal electrodes 1504,1506, the PCB assembly 1500 further includes various other electricalcomponents disposed along its length. For example, the PCB assemblyincludes each of a first intermediate electrode 1520 and a secondintermediate electrode 1522 disposed at respective locations along thePCB substrate 1502. Although other electrode shapes are contemplated,each of the first intermediate electrode 1520 and a second intermediateelectrode 1522 are illustrated as extending transversely a primarylength 1502 of the PCB substrate 1502. Such an arrangement facilitateswrapping of the intermediate electrodes 1520, 1522 about a core when thePCB assembly 1500 is assembled into a tool. As a result, when fullyassembled, the intermediate electrodes 1520, 1522 form ring-likeelectrodes extending about a core of the tool incorporating the PCBassembly 1500.

The PCB assembly 1500 further includes a sensor 1530 disposed at alocation along the PCB substrate 1502. The sensor 1530 is intended torepresent any of a wide range of sensors that may be included in the PCBassembly 1500 and that may be used to provide various measurementsduring use of a catheter including the PCB assembly 1500. For example,and without limitation, the sensor 1530 may be any of an accelerometer(e.g., for measuring position, orientation, movement, etc., of thecatheter); a pressure, temperature, or flow sensor (e.g., for measuringconditions within a physiological lumen within which the catheter isdisposed); or a sensor adapted to measure electrical activity inadjacent tissue. The sensor 1530 may be one of multiple sensorsdistributed along the PCB substrate 1502.

As illustrated in FIG. 15, each of the electrical components of the PCBassembly 1502 may include one or more respective traces connecting thecomponent to a corresponding contact pad. For example, electrodes 1504,1506, 1520, and 1522 are illustrated as being electrically coupled tocontact pads 1540A-1540D by traces 1542A-1542D and sensor 1530 isillustrated as being electrically coupled to contact pad 1540E by trace1542E. As previously noted, when assembled into a catheter, the contactpads 1540A-1540E may be electrically coupled to electrical components ofa catheter hub including one or more connectors for coupling thecatheter to computing devices, monitors, or similar systems. As analternative to the contact pads 1540A-1540D, the traces 1542A-1542E maybe extended off of the PCB substrate 1502, may be replaced by aconnector or terminal block, or may otherwise be terminated.

FIG. 16 is a flow chart illustrating a method 1600 of assembly a toolincluding a flexible PCB assembly, such as the flexible PCB assembliesillustrated in FIGS. 10-15. The method 1600 may be used to manufactureand assembly various types of tools; however, in at least certainimplementations, the tool may be a catheter, guide wire, or otherelongate tool adapted for insertion into a physiological lumen of apatient.

At operation 1602, a core of the tool is obtained. As previouslydiscussed, the term “core” is used herein to generally refer to an innerstructure of the tool. The core may have various constructions.Obtaining the core may include obtaining a prefabricated core or mayinclude at least partially forming the core.

At operation 1604, a flexible PCB assembly is disposed on the core andat operation 1606 the flexible PCB assembly is coupled to the core. Incertain implementations, the flexible PCB assembly may include anadhesive-backed PCB substrate such that disposing of the PCB assemblyonto the core generally includes laying the PCB substrate on the core,thereby bonding the PCB assembly to the core. Similarly, an adhesive mayfirst be applied to the core followed by disposition of the flexible PCBassembly onto the core. In either case, operations 1604 and 1606generally overlap in that placing the flexible PCB assembly onto thecore and coupling the flexible PCB assembly to the core.

In other implementations, operations 1604 and 1606 may be distinct stepssuch that the flexible PCB assembly is first disposed onto the core andthen coupled to the core. Coupling of the flexible PCB assembly to thecore may include applying adhesive tape, ties, clips, or any othersuitable method. Coupling may further include heat-activating or curingan adhesive disposed between the flexible PCB assembly and the core.

In operation 1608, a sheath is wrapped about the flexible PCB assemblyand the core. In one example implementation, wrapping of the sheathincludes heat-shrinking/reflowing the sheath about the flexible PCBassembly and core. It should be appreciated that wrapping of the sheathabout the flexible PCB assembly and the core may also be used to couplethe flexible PCB assembly to the core and, as a result, at least aportion of operation 1606 and operation 1606 may occur simultaneously.

In operation 1610, a portion of the sheath is removed to exposeelectronic components of the flexible PCB assembly, such as electrodes.Removal of the portion of the sheath may be performed by cutting awaythe portion of the sheath, laser ablating the portion of the sheath, orany other suitable material for removing the portion of the sheath.

Other Applications and Considerations

The previously discussed implementations of the previous disclosurefocused primarily on applications involving catheters; however, itshould be appreciated that aspects of the present disclosure are moregenerally applicable to any elongate tool that may be inserted into aphysiological lumen of a patient. For example, and without limitation,the various PCB assemblies discussed herein may be readily adapted foruse with a guide wire where the body of the guide wire forms the core ofthe tool.

It should also be appreciated that while implementations of the presentdisclosure primarily focus on electrodes disposed at a distal end of acatheter, the concepts discussed herein may be more generally applied toany electronic components disposed along the length of a catheter orsimilar elongate tool, implementations of the present disclosure maymore generally include one or more electronic components coupled to aPCB substrate and disposed at any location along an elongate body of atool. Such electronic components may include, but are not necessarilylimited to electrodes, sensors, transmitters, receivers, gauges,switches, transducers, detectors, and antennas.

The foregoing merely illustrates the principles of the presentdisclosure. Various modifications and alterations to the describedillustrative embodiments will be apparent to those skilled in the art inview of the teachings herein. It will thus be appreciated that thoseskilled in the art will be able to devise numerous systems, arrangementsand methods which, although not explicitly shown or described herein,embody the principles of the disclosure and are thus within the spiritand scope of the present disclosure. From the above description anddrawings, it will be understood by those of ordinary skill in the artthat the particular embodiments shown and described are for purposes ofillustrations only and are not intended to limit the scope of thepresent invention. References to details of particular embodiments arenot intended to limit the scope of the invention.

What is claimed is:
 1. A tool adapted for insertion into a physiologicallumen of a patient the tool comprising: a hub; a tubular core extendingdistally from the hub; a PCB substrate coupled to the tubular core,wherein the PCB substrate is preformed into a ring shape; and anelectronic component disposed on the PCB substrate and electricallycoupled to the hub; and an outer sheath disposed about each of the coreand the PCB assembly, wherein the PCB substrate is coupled to a distalend of the core by the outer sheath.
 2. The tool of claim 1, wherein thePCB substrate is flexible and wrapped about a portion of the core. 3.The tool of claim 2, wherein the PCB substrate includes an adhesivebacking and is coupled to the core by the adhesive backing.
 4. The toolof claim 2, wherein the PCB assembly further includes a terminal pointand a trace extending along the PCB substrate, the trace electricallycoupling the terminal point to the electronic component and the terminalpoint electrically coupled to the hub such that the electronic componentis electrically coupled to the hub.
 5. The tool of claim 4, wherein thePCB substrate extends distally from a proximal end of the core, theterminal point is disposed at the proximal end of the core, and theelectronic component is disposed distally from the terminal point. 6.The tool of claim 1, wherein the electronic component is an electrode.7. The tool of claim 6, wherein the electrode is disposed at a distalend of the core.
 8. The tool of claim 6, wherein the electrode extendscircumferentially about the tubular core.
 9. The tool of claim 1,wherein the PCB substrate is coupled to a distal end of the core suchthat the PCB substrate extends distally from the distal end of the core.10. The tool of claim 1, wherein the PCB substrate is a multi-part ring.11. The tool of claim 1, wherein the tubular core is a catheter shaft.12. The tool of claim 1, wherein the electronic component is a sensor.13. A catheter assembly comprising: a hub; a tubular core extendingdistally from the hub; a printed circuit board (PCB) assemblycomprising: a PCB substrate coupled to the tubular core by an adhesivebacking of the PCB substrate; a first electrode disposed on the PCBsubstrate and electrically coupled to a first terminal point of the PCBassembly; a second electrode disposed on the PCB substrate andelectrically coupled to a second terminal point of the PCB assembly; andan outer sheath disposed about each of the tubular core and the PCBassembly; wherein each of the first terminal point and the secondterminal point are electrically coupled to the hub and each of the firstelectrode and the second electrode are exposed through the outer sheath.